Keystroke tactility arrangement on a smooth touch surface

ABSTRACT

Disclosed are four arrangements for providing tactility on a touch surface keyboard. One approach is to provide tactile feedback mechanisms, such as dots, bars, or other shapes on all or many keys. In another embodiment, an articulating frame may be provided that extends when the surface is being used in a typing mode and retracts when the surface is used in some other mode, e.g., a pointing mode. The articulating frame may provide key edge ridges that define the boundaries of the key regions or may provide tactile feedback mechanisms within the key regions. The articulating frame may also be configured to cause concave depressions similar to mechanical key caps in the surface. In another embodiment, a rigid, non-articulating frame may be provided beneath the surface. A user will then feel higher resistance when pressing away from the key centers, but will feel a softer resistance at the key center.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division of U.S. patent application Ser. No.11/380,109, filed Apr. 25, 2006, which is related to the followingpatents and patent applications, which are all herein incorporated byreference: (1) U.S. Pat. No. 6,323,846, titled “Method and Apparatus forIntegrating Manual Input,” issued on Jul. 1, 2002; (2) U.S. Pat. No.6,677,932, titled “System and Method for Recognizing Touch Typing UnderLimited Tactile Feedback Conditions,” issued on Jan. 13, 2004; and (3)U.S. Pat. No. 6,570,557, titled “Multi-Touch System and Method forEmulating Modifier Keys Via Fingertip Chords,” issued on May 27, 2003.

BACKGROUND

Integration of typing, pointing, and gesture capabilities into touchsurfaces offers many advantages, such as eliminating need for mouse as aseparate pointing device, eliminating wasteful reaches between keyboardand pointing device, and general workflow streamlining. However,pointing and typing have opposite tactile feedback needs. Specifically,pointing and gesturing inputs are best accomplished using a smooth,nearly frictionless touch surface. Conversely, typists are accustomed torelying on sharp key edges for tactile feedback.

User acceptance of the TouchStream™ integrated typing, pointing andgesture input devices manufactured by FingerWorks demonstrated thatlearning to type on a smooth, un-textured surface is possible, but takessubstantial practice. In many ways, typing on such a surface is almostlike learning to type all over again. It is believed that mainstreamacceptance of typing on touch surfaces will require shortening of thetyping re-acclimation period, which, in turn, requires improvedkeystroke tactility.

Traditionally, keystroke tactility on a surface or “membrane” keyboardhas been provided by indicating key edges using hydroformed or stampedraised ridges into the surface plastic. However, this technique hasseveral disadvantages for touch surfaces also intended for pointing andgesture. For example, the key-edge ridges impede lateral pointingmotions, giving the surface a rough washboard feel. The ridges alsodisrupt position interpolation from capacitive sensor arrays as thefingertip flesh lifts over the ridge.

In a more successful attempt to provide surface keyboard users withsuitable tactile feedback, keyboards incorporating home row dimples asdisclosed in U.S. Pat. No. 6,323,846, referenced above, were produced.These dimples helped users find the home row keys when hands wereresting on the surface, while minimizing disruption of a user's motionin pointing or gesturing on the surface. However, these dimples wereineffective feedback for helping users feel for keys away from home row,or detect when they were not striking the centers of these peripheralkeys.

Another somewhat successful prior method for aligning hands on bothsurface and traditional mechanical keyboards has been to place a singleraised Braille-like dot on an “alignment” key or on the “home row” ofkeys. For example, many mechanical keyboards features such raised dotson the “F” and “J” keys, which are the index finger home positions for atouch typist using QWERTY keyboard. As with the dimples disclosed in the'846 patent, this arrangement is useful to help align a user's hands tohome row, but does not help to correct alignment errors while reachingfor peripheral keys. Thus, a significant problem arises in attempting toprovide feedback of key positions away from the home row.

Placing alignment dots, such as the single Braille-like dot, at thecenter of every key would provide feedback for key positions away fromthe home row. However, such an arrangement would eliminate thedistinctiveness of the home row keys, and create more ambiguous feedbackfor the user. Therefore, what is needed in the art is a way to providetactility to all or at least a substantial number of keys withoutcreating such a bumpy surface that pointing and gestures areuncomfortable or unsteady.

This could be accomplished by adapting known prior art Braille displays.In this approach, tiny, individually actuated pins spread across thekeyboard could provide dynamic tactility, but at great mechanical costand complexity. Thus, what is needed to reduce cost and complexity is away to provide tactility for each key without placing individualelectromagnetic actuators under each key.

An additional issue arises in that multi-touch capacitive sensor arrays,which are often used to form the multi-touch surfaces, are typicallybuilt with row and column electrodes spanning the surface, or with rowand column drive/sense line accessing electronic buffers at eachelectrode cell. Thus whatever tactility mechanism is provided, thearrangement must be routable around the row/column electrodes or drivelines of multi-touch sensors without requiring additional circuit boardvias or layers.

Disclosed herein are a variety of techniques for providing tactilefeedback in a surface or other keyboard that address one or more ofthese deficiencies of the prior art.

SUMMARY

Disclosed herein are four arrangements for providing tactility on atouch surface keyboard. One approach is to provide tactile feedbackmechanisms, such as dots, bars, or other shapes on all or at least manykeys. Different keys or groups of keys may have different feedbackmechanisms, e.g., a first feedback mechanism may be assigned to “homerow” keys, with a second feedback mechanism assigned to keys adjacentthe home row, with a third assigned to peripheral keys, which areneither home row keys nor adjacent the home row. Alternatively, anarticulating frame may be provided that extends when the surface isbeing used in a typing mode and retracts when the surface is used insome other mode, e.g., a pointing mode. The articulating frame mayprovide key edge ridges that define the boundaries of the key regions ormay be used to provide tactile feedback mechanisms within the keyregions. The articulating frame may also be configured to cause concavedepressions similar to mechanical key caps in the surface. In anotherembodiment, a rigid, non-articulating frame may be provided beneath thesurface. A user will then feel higher resistance when pressing away fromthe key centers, but will feel a softer resistance, which may beenhanced by filling the gaps with a foam or gel material or air.

Using these arrangements, as well as individual elements of each orcombinations thereof, it is possible to provide strong tactile feedbackof each key location without impeding pointing, gestures, or relatedlateral sliding motions on the same touch surface.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may best be understood by reference to the followingdescription taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is a top view of a surface keyboard employing a tactile feedbackmechanism.

FIG. 2 is a cross-section view of the surface keyboard depicted in FIG.1.

FIG. 3 is a top view of a surface keyboard employing a variation of thetactile feedback mechanism depicted in FIGS. 1 and 2.

FIG. 4 is a cross-section view of the surface keyboard depicted in FIG.3.

FIG. 5 is a cross-section view of a surface keyboard employing analternative tactile feedback arrangement including an articulating frame(shown in an extended position).

FIG. 6 is a cross-section view of the surface keyboard illustrated inFIG. 5 with the articulating frame shown in a retracted position.

FIG. 7 is a plan view of the surface keyboard illustrated in FIGS. 5 and6.

FIGS. 8A and 8B illustrate a cross-section view of a surface keyboardtactile feedback arrangement for simulating concave key cap centers.

FIG. 9 illustrates a cross-section view of a surface keyboard employinga deformable material beneath the keys to provide tactile feedback.

DETAILED DESCRIPTION

Braille-Like Dot Pairs or Bars at Key Centers

With reference now to FIGS. 1 and 2, one technique for providing tactilefeedback in a surface keyboard is depicted. FIG. 1 is a vertical view ofa surface keyboard 100. FIG. 2 is a cross-section view of surfacekeyboard 100. Surface keyboard 100 includes numerous key regions 101. Asused herein, the term “key” may also refer to the key regions 101,although in a surface keyboard there is actually no mechanical key.Rather, sensing circuitry 111 disposed beneath the surface cover 112detects an object, such as a user's finger, in contact or closeproximity with the key regions 101 and outputs the corresponding letter,number, or symbol to a host computer or other device (not shown). Thekey layout shown in FIG. 1 is a slightly modified QWERTY layout, whichhas been ergonomically designed to provide a more comfortable typingposition.

Key regions 101 are arranged in a plurality of rows. As known to touchtypists, the row of keys containing the letters “ASDF” on the left-handside and “JKL;” on the right-hand side are known as the home row 102.The home row is so called because a touch typist will keep the fourfingers of each hand over these characters when a finger is not reachingfor a key in another row. Adjacent rows 103 are the rows immediatelyadjacent, for example, the rows containing “QWER” and “ZXCV.” Theremaining rows are known as peripheral rows 104, for example, the row ofnumber keys.

One mechanism to provide more robust tactile feedback for a user of asurface keyboard is to stamp two horizontally aligned dots 105 at thecenter of each home row key 106. Similarly, two vertically aligned dots107 may be stamped on each adjacent key 108. Finally, a single dot 109may be stamped on peripheral keys 110. Because the home row keys feeldifferent than all other keys, home row 102 may be easily found withoutlooking when sliding hands over the surface. The two vertical dots 107on adjacent keys 108 in turn help distinguish their feel from peripheralnumber and punctuation keys having only one raised dot 110.

It will be appreciated that the particular arrangement of dots couldvary from that described. For example, a single dot could be used tomark home row keys 102, with two horizontal dots used for adjacent keys103 and two vertical dots used for peripheral keys 104. All that isrequired is that one unique tactile feedback mechanism, such as raiseddots, be used for home row keys, while another is used for adjacentand/or peripheral keys. It is not required that the adjacent keys andperipheral keys employ different tactile feedback mechanisms, althoughit may be preferable to do so.

Moreover, the tactile feedback mechanism need not be limited to raiseddots. In a variation of this technique, shown in plan-view in FIG. 3 andin cross-section in FIG. 4, the a raised dot pair is replaced with araised “hyphen,” i.e., a short bar 113. The short bars 113 may be, forexample, arranged horizontally (113 a) at the centers of home row keys106 and vertically (113 b) on keys adjacent to home row 102. Peripheralkeys 110 may include a single raised dot 109. Other shapes, such assquares, circles, triangles, etc. could also be used so long as thearrangements used for home row keys 102 are distinct from those used forthe adjacent keys 103 and/or peripheral keys 104. These embodiments maybe less desirable than a raised dot pair in terms of efficient tactilityand minimizing sensor distortion. However, these raised bars or othershapes may be more aesthetically pleasing than raised dot pairs.

It should also be noted that, although the tactile feedback arrangementdescribed above has particular applicability to surface keyboards, itcould also be used in conjunction with traditionalmechanical/electromechanical keyboards. Additionally, although describedin terms of the traditional QWERTY keyboard, the techniques may also beapplied to other keyboard layouts, such as Dvorak keyboard, foreignlanguage keyboards, court reporting machine keyboards, and otherkeyboard-like input devices.

Articulating Frame Protrudes at Key Edges During Typing

An alternative technique for providing tactile feedback in a surfacekeyboard will now be described with respect to FIGS. 5, 6, and 7. FIGS.5 and 6 depict a cross-section view of the keyboard, while FIG. 7depicts a plan view. As illustrated in FIGS. 5 and 6, the surfacekeyboard 200 comprises a plurality of layers including an enclosure base201, the electrode circuit board 202, and the surface cover 203. Detailsof the construction of these devices are described in the variousincorporated references and are not repeated here.

Additionally, the keyboard 200 includes an articulating frame 204, whichis disposed beneath the circuit board 202. The articulating frame 204may be raised and lowered by actuators 205, which preferably take theform of electromagnetic actuators. Raising and lowering the articulatingframe extends and withdraws key edge ridges 206, which are dots or barsthat poke through the keyboard surface when extended. Electromagneticactuators 205 would raise the frame when operating in a typing mode suchthat the tops of the key edge ridges 206 are about 1 mm above thesurface cover 203. The electromagnetic actuators 205 would lower theframe when operating in a pointing/gesture mode such that the tops ofthe key edge ridges 206 are flush with surface cover 203, therebyproviding a substantially smooth surface for pointing and gesturing.Although electromagnetic actuators 205 are depicted as being disposedbeneath the frame and above the enclosure bottom, they may be disposedin any arrangement that allows them to suitably displace the frame 204and key edge ridges 206.

Preferably, each key edge comprises one to four distinct bars orBraille-like dots. When constructed in conjunction with a capacitivemulti-touch surface, the key edge ridges should separated to accommodatethe routing of the drive electrodes, which may take the form of rows,columns, or other configurations. As an alternative to key edge ridges206, the frame could cause Braille-like dots or similar markers, asdiscussed above with respect to FIGS. 1-4 to protrude through the keycenters, although this arrangement would potentially interfere withtouch detection and measurement because it would require mechanicaldevices in proximity to the key center, which is a preferred sensorlocation. In yet another alternative arrangement, articulating frame 204could be disposed above the electrode circuit board 202, although theadded separation between the surface cover 203 and the circuit board 202could complicate the touch measurement and detection.

The electromagnetic actuators may be located at the corners and/orcenter of the frame or distributed variously throughout the frame.Selection of a particular position will necessitate the determination ofa variety of design parameters, such as frame material strength, powerrouting, cost, etc., all of which would be within the abilities of oneskilled in the art having the benefit of this disclosure. The actuators205 may be activated manually, for example, by touching the surface in aparticular region, pressing a dedicated button, activating a switch,etc. Alternatively, the actuators raise and lower the frame according tomode commands from gesture and typing recognition software, such as thatdescribed in the '846 patent incorporated by reference above.

Specifically, the recognition software commands lowering of the framewhen lateral sliding gestures or mouse clicking activity chords aredetected on the surface. Alternatively, when homing chords (i.e.,placing the fingers on the home row) or asynchronous touches (typingactivity) is detected on the surface, the recognition software commandsraising of the frame. Various combinations or subsets of theserecognition techniques could also be used. For example, the device mayactivate a typing mode when homing chords or asynchronous touches aredetected and deactivate the typing mode if neither is detected for asome time interval. In this configuration the device effectivelydefaults to a pointing mode and switches to a typing mode whennecessary. Conversely, the device could activate a pointing mode whenlateral sliding gestures or mouse clicking activity is detected andswitch to a typing mode when these activities are not detected for sometime interval. In any case, the frame will change modes automaticallyfrom lowered and flush (pointing mode) to poking through the surface(typing mode) as often as the operator switches between pointing andtyping. Of course, operators who did not like the automated behaviorcould manually toggle the frame state with a pre-assigned gesture.

When extended, the key edge bars 206 provide similar tactile feel to aconventional mechanical key edge when the finger straddles two keys.However, this arrangement does not effectively simulate the concavedepression common in mechanical keycaps, which helps a typists fingerssink towards the key center. Obviously, the key edge bars 206 will onlybe felt if fingers touch way off key center. Additionally, the holes insurface cover 203 through which the key edge bars 206 extend may collectdirt and grime. However, an extension of this arrangement may be used toaddress these concerns.

Articulating Frame Deforms Surface Cover at Key Edges During Typing

Illustrated in FIGS. 8A and 8B is a variation of the articulating framearrangement discussed above with respect to FIGS. 5, 6, and 7. FIG. 8Ashows the frame in the raised (typing) position, while FIG. 8B shows theframe in the lowered (pointing, gesturing, etc.) position. In thisembodiment, the bars of articulating frame 304 protrude through thecircuit board 302, but not through the surface cover 303. When actuators305, disposed between enclosure base 301 and the articulating frame 304raise frame 304, the bars 306 lift the surface cover 303, rather thanpoking through. By tacking the surface cover 303 to the circuit board302 at the key centers, a concave keycap depression effect 307 will becreated when the frame raises. This allows a users fingers to be guidedtoward the center of each key, much like a conventional keyboard.Additionally, because there are no holes in the surface cover 303, thereis likely to be less accumulation of dirt and grime on the surface.Obviously, such an arrangement requires a more supple cover materialthan the rigid Lexan (polycarbonate) sheets often used as touchpadsurfaces, but a variety of such materials are well known to thoseskilled in the art.

Rigid Frame Under Key Edges with Compressible Key Centers

Yet another embodiment may extends the covered key edge bars and keycenter depressions while dispensing with the mechanical complexity offrame articulation. Such an embodiment is illustrated in FIG. 9. Thesurface keyboard 400 comprises the familiar layers of an enclosure base(not shown), sensing circuit board 402 (with electrodes 402 a), andsurface cover 403. The surface cover sits atop a frame including a fixednetwork of hard key-edge ridges 404, which are preferably raised about0.5-1 mm above the sensing circuit board 402. The gaps between the keyedge ridges 404 are filled with a compliant gel or foam material 405 (orpossibly even air) filling the key centers up to flush with the ridges.

This arrangement allows the surface cover 303 to drape substantiallyperfectly flat, and remain flat when under light pressure, e.g., thatfrom a pointing or dragging operation. However, when a user presses akey center, the cover would give under their finger somewhat as thefoam/gel/air material 405 is compressed, while a user pressing over akey edge would feel the hard ridge underneath. While this arrangement iselectrically and mechanically simple (with no active mechanical parts),the surface cover and key filler materials must be chosen carefully toprovide noticeable compression at key center yet be durable to wear.Additionally, the sandwich of surface cover and foam could become toothick for the capacitive sensors to properly detect through. To overcomethese deficiencies, the surface cover 303 itself could contain flexcircuitry (well known to those skilled in the art) imprinted with asuitable electrode pattern, which would dispense with the necessity ofthe electrode layer 402.

Many variations and/or combinations of the embodiments discussed hereinwill be apparent to those skilled in the art. For example, as notedabove, the articulating frame may be combined with the Braille-like dotsto form articulating Braille-like dots. Alternatively, the fixedBraille-like dots may be combined with the articulating ridges describedwith reference to FIG. 8 or with the compressible material of FIG. 9. Itshould also be noted that there are many alternative ways ofimplementing the methods and apparatuses of the present invention. It istherefore intended that the following appended claims be interpreted asincluding all such alterations, permutations, combinations andequivalents as fall within the true spirit and scope of the invention.

1. A touch sensitive surface configurable to operate as a keyboard, thetouch sensitive surface comprising: a surface cover; a touch sensitiveelectrode circuit board disposed beneath the surface cover having aplurality of holes disposed therein; an articulating frame disposedbeneath the touch sensitive electrode circuit board having integraltherewith a plurality of key edge ridges aligned with the holes in thetouch sensitive electrode circuit board; and at least one actuatordisposed between the articulating frame and an enclosure of the touchsensitive surface and configured to displace the articulating frame soas to extend the key edge ridges through the holes in the touchsensitive electrode circuit board.
 2. The touch sensitive surface ofclaim 1 wherein the surface cover includes a plurality of holes alignedwith the holes in the circuit board and wherein the actuator isconfigured to displace the articulating frame so as to extend the keyedge ridges through the holes in the surface cover.
 3. The touchsensitive surface of claim 1 wherein the surface cover is attached tothe touch sensitive electrode circuit board at a center of a key regionsuch that extending the key edge ridges through the holes in the touchsensitive electrode circuit board forms a concave depression within thekey region.
 4. A touch sensitive surface according to claim 1 whereinthe key edge ridges are extended when the device operates in a typingmode and retracted when the devices operates in a pointing mode.
 5. Atouch sensitive surface according to claim 2 wherein the key edge ridgesare extended when the device operates in a typing mode and retractedwhen the devices operates in a pointing mode.
 6. A touch sensitivesurface according to claim 3 wherein the key edge ridges are extendedwhen the device operates in a typing mode and retracted when the devicesoperates in a pointing mode.
 7. The touch sensitive surface of claim 4wherein switching between typing mode and pointing mode is accomplishedmanually.
 8. The touch sensitive surface of claim 7 wherein manualswitching is accomplished by at least one of: actuating a switch,pressing a button, touching the surface in a pre-defined region, andperforming a pre-determined gesture.
 9. The touch sensitive surface ofclaim 4 wherein switching between typing mode and pointing mode isaccomplished automatically.
 10. The touch sensitive surface of claim 9wherein at least one of the following: the typing mode is activated whenasynchronous touches are detected; the typing mode is deactivated whenasynchronous touches are no longer detected; the typing mode isactivated when homing chords are detected; the typing mode isdeactivated when homing chords are no longer detected; the pointing modeis activated when lateral sliding gestures are detected; the pointingmode is deactivated when lateral sliding gestures are detected; thepointing mode is activated when mouse clicking activity chords aredetected; and the pointing mode is deactivated when mouse clickingactivity chords are detected.
 11. The touch sensitive surface of claim 4wherein the key edge ridges comprise a plurality of distinct bars ordots.
 12. The touch sensitive surface of claim 1 wherein the key edgeridges comprise tactile feedback mechanisms located at a center of oneor more key regions.
 13. The touch sensitive surface of claim 2 whereinthe key edge ridges comprise tactile feedback mechanisms located at acenter of one or more key regions.
 14. The touch sensitive surface ofclaim 12 wherein the tactile feedback mechanisms are selected from thegroup consisting of: a single raised dot, two raised dots arrangedhorizontally, two raised dots arranged horizontally, a raised baroriented horizontally, and a raised bar oriented vertically.
 15. Thetouch sensitive surface of claim 12 wherein the tactile feedbackmechanisms comprise: a first tactile feedback mechanism for each homerow key; and an additional tactile feedback mechanism distinct from thefirst tactile feedback mechanism for at least one key adjacent a homerow key or at least one peripheral key.
 16. The touch sensitive surfaceof claim 15 wherein the additional tactile feedback mechanism comprises:a second tactile feedback mechanism for at least one key adjacent thehome row keys; and a third tactile feedback mechanism for at least oneperipheral key; wherein the second and third tactile feedback mechanismsare distinct from each other.
 17. The keyboard of claim 16 wherein: thesecond feedback mechanism is provided for each key adjacent a home rowkey; and the third feedback mechanism is provided for each peripheralkey.